Dental bleaching, also known as tooth whitening, is a common procedure in general dentistry. There are many methods available, bleaching pen, bleaching gel, and laser bleaching. Teeth whitening has become the most requested procedure in cosmetic dentistry today. The whitening shade guides are used to measure tooth color. These shades determine the effectiveness of the whitening procedure, which may vary from two to seven shades. The effects of bleaching can last for several months, but may vary depending on the lifestyle of the patient